Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[linux-2.6] / drivers / char / xilinx_hwicap / xilinx_hwicap.c
1 /*****************************************************************************
2  *
3  *     Author: Xilinx, Inc.
4  *
5  *     This program is free software; you can redistribute it and/or modify it
6  *     under the terms of the GNU General Public License as published by the
7  *     Free Software Foundation; either version 2 of the License, or (at your
8  *     option) any later version.
9  *
10  *     XILINX IS PROVIDING THIS DESIGN, CODE, OR INFORMATION "AS IS"
11  *     AS A COURTESY TO YOU, SOLELY FOR USE IN DEVELOPING PROGRAMS AND
12  *     SOLUTIONS FOR XILINX DEVICES.  BY PROVIDING THIS DESIGN, CODE,
13  *     OR INFORMATION AS ONE POSSIBLE IMPLEMENTATION OF THIS FEATURE,
14  *     APPLICATION OR STANDARD, XILINX IS MAKING NO REPRESENTATION
15  *     THAT THIS IMPLEMENTATION IS FREE FROM ANY CLAIMS OF INFRINGEMENT,
16  *     AND YOU ARE RESPONSIBLE FOR OBTAINING ANY RIGHTS YOU MAY REQUIRE
17  *     FOR YOUR IMPLEMENTATION.  XILINX EXPRESSLY DISCLAIMS ANY
18  *     WARRANTY WHATSOEVER WITH RESPECT TO THE ADEQUACY OF THE
19  *     IMPLEMENTATION, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OR
20  *     REPRESENTATIONS THAT THIS IMPLEMENTATION IS FREE FROM CLAIMS OF
21  *     INFRINGEMENT, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
22  *     FOR A PARTICULAR PURPOSE.
23  *
24  *     Xilinx products are not intended for use in life support appliances,
25  *     devices, or systems. Use in such applications is expressly prohibited.
26  *
27  *     (c) Copyright 2002 Xilinx Inc., Systems Engineering Group
28  *     (c) Copyright 2004 Xilinx Inc., Systems Engineering Group
29  *     (c) Copyright 2007-2008 Xilinx Inc.
30  *     All rights reserved.
31  *
32  *     You should have received a copy of the GNU General Public License along
33  *     with this program; if not, write to the Free Software Foundation, Inc.,
34  *     675 Mass Ave, Cambridge, MA 02139, USA.
35  *
36  *****************************************************************************/
37
38 /*
39  * This is the code behind /dev/icap* -- it allows a user-space
40  * application to use the Xilinx ICAP subsystem.
41  *
42  * The following operations are possible:
43  *
44  * open         open the port and initialize for access.
45  * release      release port
46  * write        Write a bitstream to the configuration processor.
47  * read         Read a data stream from the configuration processor.
48  *
49  * After being opened, the port is initialized and accessed to avoid a
50  * corrupted first read which may occur with some hardware.  The port
51  * is left in a desynched state, requiring that a synch sequence be
52  * transmitted before any valid configuration data.  A user will have
53  * exclusive access to the device while it remains open, and the state
54  * of the ICAP cannot be guaranteed after the device is closed.  Note
55  * that a complete reset of the core and the state of the ICAP cannot
56  * be performed on many versions of the cores, hence users of this
57  * device should avoid making inconsistent accesses to the device.  In
58  * particular, accessing the read interface, without first generating
59  * a write containing a readback packet can leave the ICAP in an
60  * inaccessible state.
61  *
62  * Note that in order to use the read interface, it is first necessary
63  * to write a request packet to the write interface.  i.e., it is not
64  * possible to simply readback the bitstream (or any configuration
65  * bits) from a device without specifically requesting them first.
66  * The code to craft such packets is intended to be part of the
67  * user-space application code that uses this device.  The simplest
68  * way to use this interface is simply:
69  *
70  * cp foo.bit /dev/icap0
71  *
72  * Note that unless foo.bit is an appropriately constructed partial
73  * bitstream, this has a high likelyhood of overwriting the design
74  * currently programmed in the FPGA.
75  */
76
77 #include <linux/version.h>
78 #include <linux/module.h>
79 #include <linux/kernel.h>
80 #include <linux/types.h>
81 #include <linux/ioport.h>
82 #include <linux/interrupt.h>
83 #include <linux/fcntl.h>
84 #include <linux/init.h>
85 #include <linux/poll.h>
86 #include <linux/proc_fs.h>
87 #include <linux/mutex.h>
88 #include <linux/sysctl.h>
89 #include <linux/version.h>
90 #include <linux/fs.h>
91 #include <linux/cdev.h>
92 #include <linux/platform_device.h>
93
94 #include <asm/io.h>
95 #include <asm/uaccess.h>
96 #include <asm/system.h>
97
98 #ifdef CONFIG_OF
99 /* For open firmware. */
100 #include <linux/of_device.h>
101 #include <linux/of_platform.h>
102 #endif
103
104 #include "xilinx_hwicap.h"
105 #include "buffer_icap.h"
106 #include "fifo_icap.h"
107
108 #define DRIVER_NAME "icap"
109
110 #define HWICAP_REGS   (0x10000)
111
112 #define XHWICAP_MAJOR 259
113 #define XHWICAP_MINOR 0
114 #define HWICAP_DEVICES 1
115
116 /* An array, which is set to true when the device is registered. */
117 static bool probed_devices[HWICAP_DEVICES];
118 static struct mutex icap_sem;
119
120 static struct class *icap_class;
121
122 #define UNIMPLEMENTED 0xFFFF
123
124 static const struct config_registers v2_config_registers = {
125         .CRC = 0,
126         .FAR = 1,
127         .FDRI = 2,
128         .FDRO = 3,
129         .CMD = 4,
130         .CTL = 5,
131         .MASK = 6,
132         .STAT = 7,
133         .LOUT = 8,
134         .COR = 9,
135         .MFWR = 10,
136         .FLR = 11,
137         .KEY = 12,
138         .CBC = 13,
139         .IDCODE = 14,
140         .AXSS = UNIMPLEMENTED,
141         .C0R_1 = UNIMPLEMENTED,
142         .CSOB = UNIMPLEMENTED,
143         .WBSTAR = UNIMPLEMENTED,
144         .TIMER = UNIMPLEMENTED,
145         .BOOTSTS = UNIMPLEMENTED,
146         .CTL_1 = UNIMPLEMENTED,
147 };
148
149 static const struct config_registers v4_config_registers = {
150         .CRC = 0,
151         .FAR = 1,
152         .FDRI = 2,
153         .FDRO = 3,
154         .CMD = 4,
155         .CTL = 5,
156         .MASK = 6,
157         .STAT = 7,
158         .LOUT = 8,
159         .COR = 9,
160         .MFWR = 10,
161         .FLR = UNIMPLEMENTED,
162         .KEY = UNIMPLEMENTED,
163         .CBC = 11,
164         .IDCODE = 12,
165         .AXSS = 13,
166         .C0R_1 = UNIMPLEMENTED,
167         .CSOB = UNIMPLEMENTED,
168         .WBSTAR = UNIMPLEMENTED,
169         .TIMER = UNIMPLEMENTED,
170         .BOOTSTS = UNIMPLEMENTED,
171         .CTL_1 = UNIMPLEMENTED,
172 };
173 static const struct config_registers v5_config_registers = {
174         .CRC = 0,
175         .FAR = 1,
176         .FDRI = 2,
177         .FDRO = 3,
178         .CMD = 4,
179         .CTL = 5,
180         .MASK = 6,
181         .STAT = 7,
182         .LOUT = 8,
183         .COR = 9,
184         .MFWR = 10,
185         .FLR = UNIMPLEMENTED,
186         .KEY = UNIMPLEMENTED,
187         .CBC = 11,
188         .IDCODE = 12,
189         .AXSS = 13,
190         .C0R_1 = 14,
191         .CSOB = 15,
192         .WBSTAR = 16,
193         .TIMER = 17,
194         .BOOTSTS = 18,
195         .CTL_1 = 19,
196 };
197
198 /**
199  * hwicap_command_desync - Send a DESYNC command to the ICAP port.
200  * @drvdata: a pointer to the drvdata.
201  *
202  * This command desynchronizes the ICAP After this command, a
203  * bitstream containing a NULL packet, followed by a SYNCH packet is
204  * required before the ICAP will recognize commands.
205  */
206 static int hwicap_command_desync(struct hwicap_drvdata *drvdata)
207 {
208         u32 buffer[4];
209         u32 index = 0;
210
211         /*
212          * Create the data to be written to the ICAP.
213          */
214         buffer[index++] = hwicap_type_1_write(drvdata->config_regs->CMD) | 1;
215         buffer[index++] = XHI_CMD_DESYNCH;
216         buffer[index++] = XHI_NOOP_PACKET;
217         buffer[index++] = XHI_NOOP_PACKET;
218
219         /*
220          * Write the data to the FIFO and intiate the transfer of data present
221          * in the FIFO to the ICAP device.
222          */
223         return drvdata->config->set_configuration(drvdata,
224                         &buffer[0], index);
225 }
226
227 /**
228  * hwicap_get_configuration_register - Query a configuration register.
229  * @drvdata: a pointer to the drvdata.
230  * @reg: a constant which represents the configuration
231  *              register value to be returned.
232  *              Examples:  XHI_IDCODE, XHI_FLR.
233  * @reg_data: returns the value of the register.
234  *
235  * Sends a query packet to the ICAP and then receives the response.
236  * The icap is left in Synched state.
237  */
238 static int hwicap_get_configuration_register(struct hwicap_drvdata *drvdata,
239                 u32 reg, u32 *reg_data)
240 {
241         int status;
242         u32 buffer[6];
243         u32 index = 0;
244
245         /*
246          * Create the data to be written to the ICAP.
247          */
248         buffer[index++] = XHI_DUMMY_PACKET;
249         buffer[index++] = XHI_NOOP_PACKET;
250         buffer[index++] = XHI_SYNC_PACKET;
251         buffer[index++] = XHI_NOOP_PACKET;
252         buffer[index++] = XHI_NOOP_PACKET;
253
254         /*
255          * Write the data to the FIFO and initiate the transfer of data present
256          * in the FIFO to the ICAP device.
257          */
258         status = drvdata->config->set_configuration(drvdata,
259                                                     &buffer[0], index);
260         if (status)
261                 return status;
262
263         /* If the syncword was not found, then we need to start over. */
264         status = drvdata->config->get_status(drvdata);
265         if ((status & XHI_SR_DALIGN_MASK) != XHI_SR_DALIGN_MASK)
266                 return -EIO;
267
268         index = 0;
269         buffer[index++] = hwicap_type_1_read(reg) | 1;
270         buffer[index++] = XHI_NOOP_PACKET;
271         buffer[index++] = XHI_NOOP_PACKET;
272
273         /*
274          * Write the data to the FIFO and intiate the transfer of data present
275          * in the FIFO to the ICAP device.
276          */
277         status = drvdata->config->set_configuration(drvdata,
278                         &buffer[0], index);
279         if (status)
280                 return status;
281
282         /*
283          * Read the configuration register
284          */
285         status = drvdata->config->get_configuration(drvdata, reg_data, 1);
286         if (status)
287                 return status;
288
289         return 0;
290 }
291
292 static int hwicap_initialize_hwicap(struct hwicap_drvdata *drvdata)
293 {
294         int status;
295         u32 idcode;
296
297         dev_dbg(drvdata->dev, "initializing\n");
298
299         /* Abort any current transaction, to make sure we have the
300          * ICAP in a good state. */
301         dev_dbg(drvdata->dev, "Reset...\n");
302         drvdata->config->reset(drvdata);
303
304         dev_dbg(drvdata->dev, "Desync...\n");
305         status = hwicap_command_desync(drvdata);
306         if (status)
307                 return status;
308
309         /* Attempt to read the IDCODE from ICAP.  This
310          * may not be returned correctly, due to the design of the
311          * hardware.
312          */
313         dev_dbg(drvdata->dev, "Reading IDCODE...\n");
314         status = hwicap_get_configuration_register(
315                         drvdata, drvdata->config_regs->IDCODE, &idcode);
316         dev_dbg(drvdata->dev, "IDCODE = %x\n", idcode);
317         if (status)
318                 return status;
319
320         dev_dbg(drvdata->dev, "Desync...\n");
321         status = hwicap_command_desync(drvdata);
322         if (status)
323                 return status;
324
325         return 0;
326 }
327
328 static ssize_t
329 hwicap_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
330 {
331         struct hwicap_drvdata *drvdata = file->private_data;
332         ssize_t bytes_to_read = 0;
333         u32 *kbuf;
334         u32 words;
335         u32 bytes_remaining;
336         int status;
337
338         status = mutex_lock_interruptible(&drvdata->sem);
339         if (status)
340                 return status;
341
342         if (drvdata->read_buffer_in_use) {
343                 /* If there are leftover bytes in the buffer, just */
344                 /* return them and don't try to read more from the */
345                 /* ICAP device. */
346                 bytes_to_read =
347                         (count < drvdata->read_buffer_in_use) ? count :
348                         drvdata->read_buffer_in_use;
349
350                 /* Return the data currently in the read buffer. */
351                 if (copy_to_user(buf, drvdata->read_buffer, bytes_to_read)) {
352                         status = -EFAULT;
353                         goto error;
354                 }
355                 drvdata->read_buffer_in_use -= bytes_to_read;
356                 memmove(drvdata->read_buffer,
357                        drvdata->read_buffer + bytes_to_read,
358                        4 - bytes_to_read);
359         } else {
360                 /* Get new data from the ICAP, and return was was requested. */
361                 kbuf = (u32 *) get_zeroed_page(GFP_KERNEL);
362                 if (!kbuf) {
363                         status = -ENOMEM;
364                         goto error;
365                 }
366
367                 /* The ICAP device is only able to read complete */
368                 /* words.  If a number of bytes that do not correspond */
369                 /* to complete words is requested, then we read enough */
370                 /* words to get the required number of bytes, and then */
371                 /* save the remaining bytes for the next read. */
372
373                 /* Determine the number of words to read, rounding up */
374                 /* if necessary. */
375                 words = ((count + 3) >> 2);
376                 bytes_to_read = words << 2;
377
378                 if (bytes_to_read > PAGE_SIZE)
379                         bytes_to_read = PAGE_SIZE;
380
381                 /* Ensure we only read a complete number of words. */
382                 bytes_remaining = bytes_to_read & 3;
383                 bytes_to_read &= ~3;
384                 words = bytes_to_read >> 2;
385
386                 status = drvdata->config->get_configuration(drvdata,
387                                 kbuf, words);
388
389                 /* If we didn't read correctly, then bail out. */
390                 if (status) {
391                         free_page((unsigned long)kbuf);
392                         goto error;
393                 }
394
395                 /* If we fail to return the data to the user, then bail out. */
396                 if (copy_to_user(buf, kbuf, bytes_to_read)) {
397                         free_page((unsigned long)kbuf);
398                         status = -EFAULT;
399                         goto error;
400                 }
401                 memcpy(drvdata->read_buffer,
402                        kbuf,
403                        bytes_remaining);
404                 drvdata->read_buffer_in_use = bytes_remaining;
405                 free_page((unsigned long)kbuf);
406         }
407         status = bytes_to_read;
408  error:
409         mutex_unlock(&drvdata->sem);
410         return status;
411 }
412
413 static ssize_t
414 hwicap_write(struct file *file, const char __user *buf,
415                 size_t count, loff_t *ppos)
416 {
417         struct hwicap_drvdata *drvdata = file->private_data;
418         ssize_t written = 0;
419         ssize_t left = count;
420         u32 *kbuf;
421         ssize_t len;
422         ssize_t status;
423
424         status = mutex_lock_interruptible(&drvdata->sem);
425         if (status)
426                 return status;
427
428         left += drvdata->write_buffer_in_use;
429
430         /* Only write multiples of 4 bytes. */
431         if (left < 4) {
432                 status = 0;
433                 goto error;
434         }
435
436         kbuf = (u32 *) __get_free_page(GFP_KERNEL);
437         if (!kbuf) {
438                 status = -ENOMEM;
439                 goto error;
440         }
441
442         while (left > 3) {
443                 /* only write multiples of 4 bytes, so there might */
444                 /* be as many as 3 bytes left (at the end). */
445                 len = left;
446
447                 if (len > PAGE_SIZE)
448                         len = PAGE_SIZE;
449                 len &= ~3;
450
451                 if (drvdata->write_buffer_in_use) {
452                         memcpy(kbuf, drvdata->write_buffer,
453                                         drvdata->write_buffer_in_use);
454                         if (copy_from_user(
455                             (((char *)kbuf) + drvdata->write_buffer_in_use),
456                             buf + written,
457                             len - (drvdata->write_buffer_in_use))) {
458                                 free_page((unsigned long)kbuf);
459                                 status = -EFAULT;
460                                 goto error;
461                         }
462                 } else {
463                         if (copy_from_user(kbuf, buf + written, len)) {
464                                 free_page((unsigned long)kbuf);
465                                 status = -EFAULT;
466                                 goto error;
467                         }
468                 }
469
470                 status = drvdata->config->set_configuration(drvdata,
471                                 kbuf, len >> 2);
472
473                 if (status) {
474                         free_page((unsigned long)kbuf);
475                         status = -EFAULT;
476                         goto error;
477                 }
478                 if (drvdata->write_buffer_in_use) {
479                         len -= drvdata->write_buffer_in_use;
480                         left -= drvdata->write_buffer_in_use;
481                         drvdata->write_buffer_in_use = 0;
482                 }
483                 written += len;
484                 left -= len;
485         }
486         if ((left > 0) && (left < 4)) {
487                 if (!copy_from_user(drvdata->write_buffer,
488                                                 buf + written, left)) {
489                         drvdata->write_buffer_in_use = left;
490                         written += left;
491                         left = 0;
492                 }
493         }
494
495         free_page((unsigned long)kbuf);
496         status = written;
497  error:
498         mutex_unlock(&drvdata->sem);
499         return status;
500 }
501
502 static int hwicap_open(struct inode *inode, struct file *file)
503 {
504         struct hwicap_drvdata *drvdata;
505         int status;
506
507         drvdata = container_of(inode->i_cdev, struct hwicap_drvdata, cdev);
508
509         status = mutex_lock_interruptible(&drvdata->sem);
510         if (status)
511                 return status;
512
513         if (drvdata->is_open) {
514                 status = -EBUSY;
515                 goto error;
516         }
517
518         status = hwicap_initialize_hwicap(drvdata);
519         if (status) {
520                 dev_err(drvdata->dev, "Failed to open file");
521                 goto error;
522         }
523
524         file->private_data = drvdata;
525         drvdata->write_buffer_in_use = 0;
526         drvdata->read_buffer_in_use = 0;
527         drvdata->is_open = 1;
528
529  error:
530         mutex_unlock(&drvdata->sem);
531         return status;
532 }
533
534 static int hwicap_release(struct inode *inode, struct file *file)
535 {
536         struct hwicap_drvdata *drvdata = file->private_data;
537         int i;
538         int status = 0;
539
540         mutex_lock(&drvdata->sem);
541
542         if (drvdata->write_buffer_in_use) {
543                 /* Flush write buffer. */
544                 for (i = drvdata->write_buffer_in_use; i < 4; i++)
545                         drvdata->write_buffer[i] = 0;
546
547                 status = drvdata->config->set_configuration(drvdata,
548                                 (u32 *) drvdata->write_buffer, 1);
549                 if (status)
550                         goto error;
551         }
552
553         status = hwicap_command_desync(drvdata);
554         if (status)
555                 goto error;
556
557  error:
558         drvdata->is_open = 0;
559         mutex_unlock(&drvdata->sem);
560         return status;
561 }
562
563 static struct file_operations hwicap_fops = {
564         .owner = THIS_MODULE,
565         .write = hwicap_write,
566         .read = hwicap_read,
567         .open = hwicap_open,
568         .release = hwicap_release,
569 };
570
571 static int __devinit hwicap_setup(struct device *dev, int id,
572                 const struct resource *regs_res,
573                 const struct hwicap_driver_config *config,
574                 const struct config_registers *config_regs)
575 {
576         dev_t devt;
577         struct hwicap_drvdata *drvdata = NULL;
578         int retval = 0;
579
580         dev_info(dev, "Xilinx icap port driver\n");
581
582         mutex_lock(&icap_sem);
583
584         if (id < 0) {
585                 for (id = 0; id < HWICAP_DEVICES; id++)
586                         if (!probed_devices[id])
587                                 break;
588         }
589         if (id < 0 || id >= HWICAP_DEVICES) {
590                 mutex_unlock(&icap_sem);
591                 dev_err(dev, "%s%i too large\n", DRIVER_NAME, id);
592                 return -EINVAL;
593         }
594         if (probed_devices[id]) {
595                 mutex_unlock(&icap_sem);
596                 dev_err(dev, "cannot assign to %s%i; it is already in use\n",
597                         DRIVER_NAME, id);
598                 return -EBUSY;
599         }
600
601         probed_devices[id] = 1;
602         mutex_unlock(&icap_sem);
603
604         devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR + id);
605
606         drvdata = kzalloc(sizeof(struct hwicap_drvdata), GFP_KERNEL);
607         if (!drvdata) {
608                 dev_err(dev, "Couldn't allocate device private record\n");
609                 retval = -ENOMEM;
610                 goto failed0;
611         }
612         dev_set_drvdata(dev, (void *)drvdata);
613
614         if (!regs_res) {
615                 dev_err(dev, "Couldn't get registers resource\n");
616                 retval = -EFAULT;
617                 goto failed1;
618         }
619
620         drvdata->mem_start = regs_res->start;
621         drvdata->mem_end = regs_res->end;
622         drvdata->mem_size = regs_res->end - regs_res->start + 1;
623
624         if (!request_mem_region(drvdata->mem_start,
625                                         drvdata->mem_size, DRIVER_NAME)) {
626                 dev_err(dev, "Couldn't lock memory region at %Lx\n",
627                         regs_res->start);
628                 retval = -EBUSY;
629                 goto failed1;
630         }
631
632         drvdata->devt = devt;
633         drvdata->dev = dev;
634         drvdata->base_address = ioremap(drvdata->mem_start, drvdata->mem_size);
635         if (!drvdata->base_address) {
636                 dev_err(dev, "ioremap() failed\n");
637                 goto failed2;
638         }
639
640         drvdata->config = config;
641         drvdata->config_regs = config_regs;
642
643         mutex_init(&drvdata->sem);
644         drvdata->is_open = 0;
645
646         dev_info(dev, "ioremap %lx to %p with size %Lx\n",
647                  (unsigned long int)drvdata->mem_start,
648                         drvdata->base_address, drvdata->mem_size);
649
650         cdev_init(&drvdata->cdev, &hwicap_fops);
651         drvdata->cdev.owner = THIS_MODULE;
652         retval = cdev_add(&drvdata->cdev, devt, 1);
653         if (retval) {
654                 dev_err(dev, "cdev_add() failed\n");
655                 goto failed3;
656         }
657         /*  devfs_mk_cdev(devt, S_IFCHR|S_IRUGO|S_IWUGO, DRIVER_NAME); */
658         device_create(icap_class, dev, devt, "%s%d", DRIVER_NAME, id);
659         return 0;               /* success */
660
661  failed3:
662         iounmap(drvdata->base_address);
663
664  failed2:
665         release_mem_region(regs_res->start, drvdata->mem_size);
666
667  failed1:
668         kfree(drvdata);
669
670  failed0:
671         mutex_lock(&icap_sem);
672         probed_devices[id] = 0;
673         mutex_unlock(&icap_sem);
674
675         return retval;
676 }
677
678 static struct hwicap_driver_config buffer_icap_config = {
679         .get_configuration = buffer_icap_get_configuration,
680         .set_configuration = buffer_icap_set_configuration,
681         .get_status = buffer_icap_get_status,
682         .reset = buffer_icap_reset,
683 };
684
685 static struct hwicap_driver_config fifo_icap_config = {
686         .get_configuration = fifo_icap_get_configuration,
687         .set_configuration = fifo_icap_set_configuration,
688         .get_status = fifo_icap_get_status,
689         .reset = fifo_icap_reset,
690 };
691
692 static int __devexit hwicap_remove(struct device *dev)
693 {
694         struct hwicap_drvdata *drvdata;
695
696         drvdata = (struct hwicap_drvdata *)dev_get_drvdata(dev);
697
698         if (!drvdata)
699                 return 0;
700
701         device_destroy(icap_class, drvdata->devt);
702         cdev_del(&drvdata->cdev);
703         iounmap(drvdata->base_address);
704         release_mem_region(drvdata->mem_start, drvdata->mem_size);
705         kfree(drvdata);
706         dev_set_drvdata(dev, NULL);
707
708         mutex_lock(&icap_sem);
709         probed_devices[MINOR(dev->devt)-XHWICAP_MINOR] = 0;
710         mutex_unlock(&icap_sem);
711         return 0;               /* success */
712 }
713
714 static int __devinit hwicap_drv_probe(struct platform_device *pdev)
715 {
716         struct resource *res;
717         const struct config_registers *regs;
718         const char *family;
719
720         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
721         if (!res)
722                 return -ENODEV;
723
724         /* It's most likely that we're using V4, if the family is not
725            specified */
726         regs = &v4_config_registers;
727         family = pdev->dev.platform_data;
728
729         if (family) {
730                 if (!strcmp(family, "virtex2p")) {
731                         regs = &v2_config_registers;
732                 } else if (!strcmp(family, "virtex4")) {
733                         regs = &v4_config_registers;
734                 } else if (!strcmp(family, "virtex5")) {
735                         regs = &v5_config_registers;
736                 }
737         }
738
739         return hwicap_setup(&pdev->dev, pdev->id, res,
740                         &buffer_icap_config, regs);
741 }
742
743 static int __devexit hwicap_drv_remove(struct platform_device *pdev)
744 {
745         return hwicap_remove(&pdev->dev);
746 }
747
748 static struct platform_driver hwicap_platform_driver = {
749         .probe = hwicap_drv_probe,
750         .remove = hwicap_drv_remove,
751         .driver = {
752                 .owner = THIS_MODULE,
753                 .name = DRIVER_NAME,
754         },
755 };
756
757 /* ---------------------------------------------------------------------
758  * OF bus binding
759  */
760
761 #if defined(CONFIG_OF)
762 static int __devinit
763 hwicap_of_probe(struct of_device *op, const struct of_device_id *match)
764 {
765         struct resource res;
766         const unsigned int *id;
767         const char *family;
768         int rc;
769         const struct hwicap_driver_config *config = match->data;
770         const struct config_registers *regs;
771
772         dev_dbg(&op->dev, "hwicap_of_probe(%p, %p)\n", op, match);
773
774         rc = of_address_to_resource(op->node, 0, &res);
775         if (rc) {
776                 dev_err(&op->dev, "invalid address\n");
777                 return rc;
778         }
779
780         id = of_get_property(op->node, "port-number", NULL);
781
782         /* It's most likely that we're using V4, if the family is not
783            specified */
784         regs = &v4_config_registers;
785         family = of_get_property(op->node, "xlnx,family", NULL);
786
787         if (family) {
788                 if (!strcmp(family, "virtex2p")) {
789                         regs = &v2_config_registers;
790                 } else if (!strcmp(family, "virtex4")) {
791                         regs = &v4_config_registers;
792                 } else if (!strcmp(family, "virtex5")) {
793                         regs = &v5_config_registers;
794                 }
795         }
796         return hwicap_setup(&op->dev, id ? *id : -1, &res, config,
797                         regs);
798 }
799
800 static int __devexit hwicap_of_remove(struct of_device *op)
801 {
802         return hwicap_remove(&op->dev);
803 }
804
805 /* Match table for of_platform binding */
806 static const struct of_device_id __devinitconst hwicap_of_match[] = {
807         { .compatible = "xlnx,opb-hwicap-1.00.b", .data = &buffer_icap_config},
808         { .compatible = "xlnx,xps-hwicap-1.00.a", .data = &fifo_icap_config},
809         {},
810 };
811 MODULE_DEVICE_TABLE(of, hwicap_of_match);
812
813 static struct of_platform_driver hwicap_of_driver = {
814         .owner = THIS_MODULE,
815         .name = DRIVER_NAME,
816         .match_table = hwicap_of_match,
817         .probe = hwicap_of_probe,
818         .remove = __devexit_p(hwicap_of_remove),
819         .driver = {
820                 .name = DRIVER_NAME,
821         },
822 };
823
824 /* Registration helpers to keep the number of #ifdefs to a minimum */
825 static inline int __init hwicap_of_register(void)
826 {
827         pr_debug("hwicap: calling of_register_platform_driver()\n");
828         return of_register_platform_driver(&hwicap_of_driver);
829 }
830
831 static inline void __exit hwicap_of_unregister(void)
832 {
833         of_unregister_platform_driver(&hwicap_of_driver);
834 }
835 #else /* CONFIG_OF */
836 /* CONFIG_OF not enabled; do nothing helpers */
837 static inline int __init hwicap_of_register(void) { return 0; }
838 static inline void __exit hwicap_of_unregister(void) { }
839 #endif /* CONFIG_OF */
840
841 static int __init hwicap_module_init(void)
842 {
843         dev_t devt;
844         int retval;
845
846         icap_class = class_create(THIS_MODULE, "xilinx_config");
847         mutex_init(&icap_sem);
848
849         devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
850         retval = register_chrdev_region(devt,
851                                         HWICAP_DEVICES,
852                                         DRIVER_NAME);
853         if (retval < 0)
854                 return retval;
855
856         retval = platform_driver_register(&hwicap_platform_driver);
857
858         if (retval)
859                 goto failed1;
860
861         retval = hwicap_of_register();
862
863         if (retval)
864                 goto failed2;
865
866         return retval;
867
868  failed2:
869         platform_driver_unregister(&hwicap_platform_driver);
870
871  failed1:
872         unregister_chrdev_region(devt, HWICAP_DEVICES);
873
874         return retval;
875 }
876
877 static void __exit hwicap_module_cleanup(void)
878 {
879         dev_t devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
880
881         class_destroy(icap_class);
882
883         platform_driver_unregister(&hwicap_platform_driver);
884
885         hwicap_of_unregister();
886
887         unregister_chrdev_region(devt, HWICAP_DEVICES);
888 }
889
890 module_init(hwicap_module_init);
891 module_exit(hwicap_module_cleanup);
892
893 MODULE_AUTHOR("Xilinx, Inc; Xilinx Research Labs Group");
894 MODULE_DESCRIPTION("Xilinx ICAP Port Driver");
895 MODULE_LICENSE("GPL");